Tartan or Lace?

Oh the dilemma.  Can't decide which shirt to wear.  Before you all weigh in about age and appropriateness... first of all get a life and second of all these are regular shirts we are talking about one of which has some lace attached to it and one of which has some random bits of tartan sewn onto it.  They're both Comme Des Garçons shirts and so are timeless and yet insanely fashionable, ordinary and yet eye wateringly expensive (but then don't forget I will be wearing the pony coat too - and Fig your lips are still sealed on that I hope you know): ready to wear at haute couture prices.  I've no idea what to do.  Tartan is my "Festival Shirt" and so has been seen by some before - but I love it.  Lace has only ever been worn once before so very few people will have seen it - but does that tell its own story?  Oh I don't know, turn up at the party or read the blog tomorrow to find out how I solve this conundrum.  That's all.  J x